Fig. 2

Cancer cells switch to PC-mediated anaplerosis when glutamine availability is limited. In glutamine-sufficient conditions (left panel), glutamine is converted to αKG to maintain pools of TCA cycle intermediates and their related biosynthetic reactions. When glutamine metabolism is impaired or glutamine availability is limited (right panel), cells may undergo a switch to PC-mediated anaplerosis which maintains TCA cycle intermediates under glutamine-depleted conditions. CTP, citrate transport protein; Glu, glutamate; Gln, glutamine; GLS, glutaminase; IDH1, isocitrate dehydrogenase 1; PDH, pyruvate dehydrogenase; SDH, succinate dehydrogenase